SAFE WORK PROCEDURE
LOCATION
VMC
WRITTEN BY: APPROVED BY:
Science Team
Determining Hydrogen Ion
Concentration of Strong and
Weak Acids
Page 1 of 2
DATE CREATED
WS&H
LAST REVISION
June 27, 2014
New
PERSONAL PROTECTION EQUIPMENT (PPE)
Safety glasses or face shield must be worn at all
times in work areas.
Long and loose hair must be tied back
Appropriate footwear must be worn. Shoe must
be fully enclosed. No open toed shoes.
Close fitting/protective clothing must be worn.
Remove strings hanging from pullovers/sweaters.
Rings and jewelry (long necklaces / bracelets,
etc.) must not be worn.
HAZARDS PRESENT
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Chemical burns
Absorption of Chemicals.
Inhalation of Chemicals.
Ingestion of Chemicals.
Slips / trips & falls
Chemical hazards
ADDITIONAL
REQUIREMENTS
APPARATUS / MATERIALS
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Test tubes and rack
Graduated cylinder
Pipet
Marking pencil
Distilled water
0.1M HCl
1.0M acetic acid
Methyl orange
Orange IV
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Equipment orientation
WHMIS training
SAFE WORK PROCEDURE
1. Don all personal protective equipment including: safety glasses, & protective nitrile gloves
(where required). Ensure all loose clothing is either removed or tied back. Remove any jewelry
and tie back long hair.
2. Obtain 5 ml of HCl in a small beaker. Pipette 2 ml of the HCl into a clean test tube. This is
Concentration 1 Set 1. Pipette 2 ml of the HCl into another clean test tube. This is
Concentration 1 Set 2.
3. Label the test tubes. Save the remaining 1 ml of HCl for concentration 2.
4. Using a 10 ml graduated cylinder, measure out 4.5 ml of distilled water and pour it into a clean
test tube.
5. From your 1 ml of 0.1M HCl remaining in your small beaker carefully pipette 0.5 ml into the test
tube with your 4.5 ml of water.
6. Put 2 ml of this solution into two new test tubes. This will be concentration 2 set 1 and 2.
SAFE WORK PROCEDURE
Determining Hydrogen Ion
Concentration of Strong and
Weak Acids
Page 2 of 2
7. Label these test tubes as having a concentration of 0.01M HCl.
8. Save the remaining 1 ml of 0.01M HCl for making concentration 3.
9. Using a 10 ml graduated cylinder measure out 4.5 ml of distilled water and pour it into a clean
test tube.
10. From your 1 ml of 0.01M HCl remaining pipette 0.5 ml into the test tube with your 4.5 ml of
water.
11. Put 2 ml of this solution into two new test tubes. This will be concentration 3 set 1 and 2.
12. Label these as having a concentration of 0.001M HCl.
13. Save the remaining 1 ml of 0.001M HCl for concentration 4.
14. Measure out 4.5 ml of distilled water and put it into a clean test tube.
15. Pipette 0.5 ml of 0.001M HCl into your test tube.
16. Put 2 ml of this solution into two new test tubes. This will be concentration 4 set 1 and 2.
17. Label these as having a concentration of 0.0001M HCl. The remaining 1 ml can be discarded
down the sink.
18. Add one drop of methyl orange to test tube in set 1.
19. Add one drop of orange IV indicator to each test tube in set 2.
20. These two sets of test tubes act as standard solutions because HCl is a strong acid.
21. Obtain 5 ml of the 1.0M concentration of acetic acid.
22. Put it in your rinsed small beaker. Place 2 ml of the solution into two new test tubes.
23. Add one drop of methyl orange to test tube one and one drop of orange IV to test tube 2.
24. Compare the colours of these solutions to your standard solutions to determine the
concentration of hydrogen ions.
25. Clean up your workstation.
REGULATORY REQUIREMENTS
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WS&H Act W210, Section 4, 5
Mb. Regulations 217/2006,
Part 16, (Machines / Tools & Robots) Sections 16.1-16.18)
SAFE WORK PROCEDURE
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Part 35, (WHMIS Application)
Part 36, (Chemical & Biological Substances Application)
Determining Hydrogen Ion
Concentration of Strong and
Weak Acids
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